Cloned from launchpad blueprint https://blueprints.launchpad.net/glance/+spec/glance-cache-service.

Description:

**** THIS IS A WORK IN PROGRESS IDEA ****

The idea here is to have a separate service for the cache manager. 

Scenario:

    1) glance-api running in a server (which doesn't have huge amounts of memory / disk) perhaps shared with other services that takes all requests for images / members. 

    2) glance-cache living in a server with more resources with the cached images.

    3) Glance api gets a request for "downloading" an image and routes the client to the cached node with the cached image

This will allow the user for distributing cached images, glance-api would still handle those at a higher level and would be responsible for routing the client to the right cache server and in a bigger scenario, glance could also have some heuristics to "automatically" cache the most recent / common images.

Specification URL (additional information):

None